| abstract |
A uniformly expandable hydrophilic sponge, adapted for medical usage, characterized by instantaneous wicking and a high liquid holding capacity comprising a reaction product of polyvinyl alcohol and formaldehyde. The wicking and liquid holding capacity is attained by controlling the time, temperature and processing conditions while forming and curing the reaction product in an aqueous medium. The sponge is rendered uniformly expandable by drying the wet sponge while maintaining the shape of the wet sponge. The sponge can be made X-ray opaque by incorporating, homogeneously, throughout an encapsulated radiopaque substance with the formaldehyde and polyvinyl alcohol. The sponge is biocompatible, non-toxic, lint free, compressible, resilient, strong, non-abrasive, free of foreign leachable materials and is of exceptionally high fluid holding capacity. |